topic Re: WLC and EIRP on internal APs in Wireless

WLC and EIRP on internal APs

thefilmguy — Mon, 05 Jul 2021 19:59:09 GMT

Do the transmit power values on the controller of the APs include the EIRP rating of the internal radio AP?

Re: WLC and EIRP on internal APs

Mark Elsen — Sun, 10 Jan 2021 18:19:15 GMT

- Note that this may also depend on the antenna-type being used :

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/23231-powervalues-23231.html#irp

Re: WLC and EIRP on internal APs

thefilmguy — Mon, 11 Jan 2021 14:24:25 GMT

Already reviewed this. It does not answer the question.

Re: WLC and EIRP on internal APs

luiggi-moreira — Wed, 18 Sep 2024 18:24:47 GMT

hi @thefilmguy , did you get this reponse at some point? I also have the same doubt.
Once, a TAC engineer told me that the "show ap dot11 5ghz summary" shows already the EIRP, that is, it shows the TX Power + Antenna Gain.

However I always get to the point where I don't agree with that too much 😞

Re: WLC and EIRP on internal APs

JPavonM — Thu, 19 Sep 2024 06:45:40 GMT

"show ap dot11 5 summary" does show the actual TX power of the radio interface, nad NOT the EIRP of the system.

See this example for a C9120AXI-E:

As you can see above, the antenna gain is set to 10 (5 dBi) by default on an internal antenna system, and TX power levels are adjusted so to account for the maximum EIRP mandate on ETSI domain, which is 23 dBm.
As you can see in the previous output, the TX power level in use is level 4 (9 dBm), and from the next output, you can see that the reported power level is 9 dBm, so this definitely demostrate that the command "show ap dot11 5 summary" shows the current radio interface power, and not the EIRP, so you need to add antenna gain to taht value.

Re: WLC and EIRP on internal APs

luiggi-moreira — Thu, 19 Sep 2024 18:45:58 GMT

Thanks @JPavonM :), for your kind and very well detailed explanation.

Your explanation goes much more in line with my understanding and so I was finally able to grasp the concept with your screenshots.

Therefore, I will not forget this anymore. Thank you so much, once again!

But